I’ve always had a simple strategy for advertising on this site: no ads (except occasional ones for personal projects and good causes) on the home page or RSS feed, and plenty of ads on the ‘individual archive’ pages. In theory, regular readers view the front page and RSS feed, and searchers visit a random individual entry on the site. I don’t want to advertise to my dear regular readers (besides, you don’t click ads), but I do want to grab a chunk of the searchers’ attention.
This was an imperfect system. Readers see the individual archive pages when they comment, for example.
I recently happened upon a better solution: the Shylock AdSense plugin for WordPress. This plugin enables you to position ads within blog posts. Nothing too fancy there, I suppose, but the advantage is that you can set an option for ‘don’t display ads on pages less than x days old’.